Load-out systems for handling bulk material, such as coal, are gaining wide acceptance in the mining transportation field. It is now possible with modern load-out systems to quickly load a train of rail cars while the train is moving forward at a constant speed. This innovation has greatly enhanced the efficiency of the transportation of bulk material dramatically.
One of the most successful load-out systems is shown in U.S. Pat. No. 4,372,730, issued to Carroll H. Ladt, Feb. 8, 1983. In this system, pivoting load-out chutes feed the coal into the rail cars in a very efficient manner. With a skilled operator, the distribution of coal within the car can be made substantially evenly spaced between the supporting trucks of the car. More effective control over the coal is provided by including a curved blade gate adjacent the lower end of the chute. This system successfully loads the coal in a rapid manner without spillage while the train is proceeding at a substantially constant speed of about one-half mile per hour.
A similar arrangement for loading rail cars as the car continuously moves forward is shown in the U.S. Pat. No. 4,284,380, issued Aug. 18, 1981. In this system, the operator controls the key functions including the speed of the conveyor feeding the coal from the storage bin to the loading hopper. Depending on the skill of the operator in manually changing the conveyor speed and inclination of the feed chutes, substantially even loading of the cars can be approached as the train moves through the load-out station. Because of the limited capacity of the conveyor feeding the chute, the train in the '380 patent can move only one-half the speed as used in the hopper feed type of load-out system shown in the '730 patent.
Furthermore, the continuously running conveyor is relied upon solely to provide the regulation of the flow of material with the chute above the rail cars serving simply to channel the coal into the car. Thus, when the flow on the conveyor is uneven, as occasionally occurs, the rate of flow into the car varies, which in turn makes for uneven loading. This adds to the tedious job of the operator in trying to evenly load the car. The speed of the conveyor and/or the inclination of the chute must be temporarily adjusted in an attempt to smooth out the flow.
The necessity for utilizing an operator to continuously monitor the prior art systems, as described above, has substantially reduced their cost effectiveness. From analysis made in the industry, the need has been identified to provide a computer controlled system for bulk loading material into a rail car. In order to be accepted in the field, the computer control system should utilize the existing equipment hardware and be capable of automatically distributing the load within different size cars.